Binghald per alfbed andebsson



P 1932- R. P. A. ANDERSSON 1,875,692

ARRANGEMENT FOR ELECTRIC iNCANDESCENT LAMPS Filed April 11. 1928Patented Sept. 6, 1932 UNITED STATES ARRANGEMENT FOR ELECTRIC INCANDESQENT' LAMPS Application filed April 11, 1928, Serial No.

This invention relates to an electric incandescent lamp with a pluralityof filaments, provided with a switch for connecting the threads eachseparately or combined arbi- 5 trarily, which switch may be arrangedinside 19 to be set by means of a rotatable disc or the, like outsidethe bottom plate of the lamp cap, whereby the lamp may be connected tousual holders for lamps with a single filament. The lamp may in acertain position be connected to a special holder, by means of which ismade possible the connection of the filaments from a selecting currentswitch arranged on a wall or for instance by table lamps in the lampholder.

Fig. 1 is a vertical central sectional View of the sleeve and base andcontacts ofa lamp constructed and arranged in accordance with myinvention and showing the filaments and conductors diagrammatically.

' Fig. 2 is a similar View of a modification of the same arranged foruse with an Edison holder.

Fig. 3 is a diagrammatic plan of another modification of the invention.

Fig. l is a similar View of a holder of the same.

In the embodiment of my invention shown in Fig. 1, there is a sheetmetal sleeve as usual, v

in one end of which the neck of the bulb is secured in the usual way. Inthe bottom contact 58 is turnably arranged a pin 59, which at the lowerend ends in a collar 60, forming an abutment for one end of a helicalspring 61' around the pin, the other end of which helical spring restsagainst the under side of the bottom. contact. On the exterior of thebottom contact the pin ends with a rotatable disc 62, to which isfastened a contact spring 63, which by the turning of the disc 62 can bebrought into contact with either or both oftwo contacts 65, 66 passingthrough the bottom plate 64. Necessary contact pressure is caused by thespring 59. Conductingly connected as at 65a with one of the contacts,for instance 65, a contact ring 269,172, and in Sweden many as, ices.

67 is sunk into the bottom plate 64, which contactring isiconcentric-tothe centre axis of the lamp. The filament is connectedfat one end to oneend of the sleeve, as shown, and v a pair of filaments 6, 7, areconnected to the other end of filament 5, filament 6 being connected tothe contact and filament 7 being connected to contact 66. When the lampis to be placed] in a special holder with con nection to a selectorcurrent switch the rotat able disc is to be set in such a way that thespring '63 rests against the contact 66 alone.

In the upper part of theholder shown in TENT o F CE f- Fig. 2, a plate71 of porcelain or thelike is detachably" fastened. In the upper edge ofa sheet metal cylinder 7 2 fastened to the plate 71", in which cylinderthe'thread 73 intended for the lamp is made, is arranged a depres sion74, in which a yielding contact tongue 75 is arranged, the loweryielding contact part of which, when the lamp is removed, has a slightlyshorter centre distance than the contact ring 67 for causing thenecessary contact pressure. The tongue 75 is fastened to the plate 71and conductingly connected to one of three terminal screws 76, 77, 78 inconnection with a selector current switch, namely to 76. The tworemaining screws are connected in the usual way, one 77, to a contactdisc 79 in the center on the under side of theplate 71, the other, 78,t0 the thread 73 or the like.

Figs. 3 and 4: show the bottom plate 50 of a lamp cap seen from insideand from outside respectively with another embodiment of the switcharranged at said plate.

On the inside of'said plate are two contacts 51 and 52, which arerespectively connected with contact rings 53 and 54.- concentricallyarranged on the outside of the bottom plate. A central shaft 55 extendsthrough a central opening in the plate 50 and to said shaft'is attacheda spring 56, which spring may be brought into or out of engagement withone or both of the contacts 51 and 52 by the turning of the shaft 55 bymeans of a disc 57 fastened to that part of the shaft 55 situatedoutside the plate 50. The connecting wires 6and 7 are connected to eachone of the contacts 51, 52. Of course, the rotatable shaft may besubstituted for a tube rotatable around a central pin, said pin beinginsulated from the tube by means of a bushing and connected with one ofthe contacts 51, 52, and the'contact rings being left out.

At the connecting of the lampin a special holder, the spring 56 is firstset on that contact, which is not connected to the pin situated insidethe tube.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is:

A lamp having a metalsleeve, a base, a bottom contact on the base, a pinrotatably journaled in the bottom contact "and provided at its free endwith a collar forming an abutment, a helical spring on the pin bearingatone end against said abutment and at theother-end against the under sideof the U bottom contact", a rotatable disc fast to the outer end of thepin and "having a contact spring, a pair of contacts extending throughthe base and each engageable by said contact spring, a contact ringarranged on the outer side of the base and electrically connected to-oneof said contacts and a plurality of filamy name.

ments each having one end connected to the sleeve and the other endconnected to one of the first named contacts. 7

In witness whereof, I have hereunto signed RINGHALD'PER ALFREDANDERSSON.

